#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#include "stdint.h"
#include "sdkconfig.h"

/*
 * Include file for users of JPEG library.
 * You will need to have included system headers that define at least
 * the typedefs FILE and size_t before you can include jpeglib.h.
 * (stdio.h is sufficient on ANSI-conforming systems.)
 * You may also wish to include "jerror.h".
 */

#include "jpeglib.h"
#include "jpegd2.h"
/*
 * <setjmp.h> is used for the optional error recovery mechanism shown in
 * the second part of the example.
 */

#include <setjmp.h>

/******************** JPEG DECOMPRESSION SAMPLE INTERFACE *******************/

/* This half of the example shows how to read data from the JPEG decompressor.
 * It's a bit more refined than the above, in that we show:
 *   (a) how to modify the JPEG library's standard error-reporting behavior;
 *   (b) how to allocate workspace using the library's memory manager.
 *
 * Just to make this example a little different from the first one, we'll
 * assume that we do not intend to put the whole image into an in-memory
 * buffer, but to send it line-by-line someplace else.  We need a one-
 * scanline-high JSAMPLE array as a work buffer, and we will let the JPEG
 * memory manager allocate it for us.  This approach is actually quite useful
 * because we don't need to remember to deallocate the buffer separately: it
 * will go away automatically when the JPEG object is cleaned up.
 */


/*
 * ERROR HANDLING:
 *
 * The JPEG library's standard error handler (jerror.c) is divided into
 * several "methods" which you can override individually.  This lets you
 * adjust the behavior without duplicating a lot of code, which you might
 * have to update with each future release.
 *
 * Our example here shows how to override the "error_exit" method so that
 * control is returned to the library's caller when a fatal error occurs,
 * rather than calling exit() as the standard error_exit method does.
 *
 * We use C's setjmp/longjmp facility to return control.  This means that the
 * routine which calls the JPEG library must first execute a setjmp() call to
 * establish the return point.  We want the replacement error_exit to do a
 * longjmp().  But we need to make the setjmp buffer accessible to the
 * error_exit routine.  To do this, we make a private extension of the
 * standard JPEG error handler object.  (If we were using C++, we'd say we
 * were making a subclass of the regular error handler.)
 *
 * Here's the extended error handler struct:
 */

struct my_error_mgr {
    struct jpeg_error_mgr pub;	/* "public" fields */
    jmp_buf setjmp_buffer;	/* for return to caller */
};

typedef struct my_error_mgr *my_error_ptr;

static uint8_t  *jpegbuf;
static uint32_t jbufsize;

/*
 * Here's the routine that will replace the standard error_exit method:
 */

METHODDEF(void) my_error_exit(j_common_ptr cinfo)
{
    /* cinfo->err really points to a my_error_mgr struct, so coerce pointer */
    my_error_ptr myerr = (my_error_ptr) cinfo->err;

    /* Always display the message. */
    /* We could postpone this until after returning, if we chose. */
    (*cinfo->err->output_message)(cinfo);

    /* Return control to the setjmp point */
    longjmp(myerr->setjmp_buffer, 1);
}


//初始化资源,不执行任何操作
static void init_source(j_decompress_ptr cinfo)
{
    //不需要做任何事情.
    return;
}
//填充输入缓冲区,一次性读取整帧数据
static boolean fill_input_buffer(j_decompress_ptr cinfo)
{
    if (jbufsize == 0) { //结束了
        printf("jd read off\r\n");
        //填充结束符
        jpegbuf[0] = (uint8_t) 0xFF;
        jpegbuf[1] = (uint8_t) JPEG_EOI;
        cinfo->src->next_input_byte = jpegbuf;
        cinfo->src->bytes_in_buffer = 2;
    } else {
        cinfo->src->next_input_byte = jpegbuf;
        cinfo->src->bytes_in_buffer = jbufsize;
        jbufsize -= jbufsize;
    }

    return TRUE;
}

//在文件里面,跳过num_bytes个数据
static void skip_input_data(j_decompress_ptr cinfo, long num_bytes)
{
    /* Just a dumb implementation for now.  Could use fseek() except
    * it doesn't work on pipes.  Not clear that being smart is worth
    * any trouble anyway --- large skips are infrequent.
    */
    if (num_bytes > 0) {
        while (num_bytes > (long) cinfo->src->bytes_in_buffer) {
            num_bytes -= (long)cinfo->src->bytes_in_buffer;
            (void)cinfo->src->fill_input_buffer(cinfo);
            /* note we assume that fill_input_buffer will never
            * return FALSE, so suspension need not be handled.
            */
        }

        cinfo->src->next_input_byte += (size_t) num_bytes;
        cinfo->src->bytes_in_buffer -= (size_t) num_bytes;
    }
}

//在解码结束后,被jpeg_finish_decompress函数调用
static void term_source(j_decompress_ptr cinfo)
{
    //不做任何处理
    return;
}

//初始化jpeg解码数据源
static void jpeg_filerw_src_init(j_decompress_ptr cinfo)
{
    if (cinfo->src == NULL) {   /* first time for this JPEG object? */
        cinfo->src = (struct jpeg_source_mgr *)
                     (*cinfo->mem->alloc_small)((j_common_ptr) cinfo, JPOOL_PERMANENT,
                                                sizeof(struct jpeg_source_mgr));
    }

    cinfo->src->init_source = init_source;
    cinfo->src->fill_input_buffer = fill_input_buffer;
    cinfo->src->skip_input_data = skip_input_data;
    cinfo->src->resync_to_restart = jpeg_resync_to_restart; /* use default method */
    cinfo->src->term_source = term_source;
    cinfo->src->bytes_in_buffer = 0; /* forces fill_input_buffer on first read */
    cinfo->src->next_input_byte = NULL; /* until buffer loaded */
}

/*
 * Sample routine for JPEG decompression.  We assume that the source file name
 * is passed in.  We want to return 1 on success, 0 on error.
 */
void mjpegdraw(uint8_t *mjpegbuffer, uint32_t size, uint8_t *outbuffer, lcd_write_cb lcd_cb)
{
    /* This struct contains the JPEG decompression parameters and pointers to
     * working space (which is allocated as needed by the JPEG library).
     */
    struct jpeg_decompress_struct cinfo;
    /* We use our private extension JPEG error handler.
     * Note that this struct must live as long as the main JPEG parameter
     * struct, to avoid dangling-pointer problems.
     */
    struct my_error_mgr jerr;
    /* More stuff */
    JSAMPARRAY buffer;		/* Output row buffer */
    int row_stride;		/* physical row width in output buffer */

    /* In this example we want to open the input file before doing anything else,
     * so that the setjmp() error recovery below can assume the file is open.
     * VERY IMPORTANT: use "b" option to fopen() if you are on a machine that
     * requires it in order to read binary files.
     */
    jpegbuf = mjpegbuffer;
    jbufsize = size;

    /* Step 1: allocate and initialize JPEG decompression object */

    /* We set up the normal JPEG error routines, then override error_exit. */
    cinfo.err = jpeg_std_error(&jerr.pub);
    jerr.pub.error_exit = my_error_exit;

    /* Establish the setjmp return context for my_error_exit to use. */
    if (setjmp(jerr.setjmp_buffer)) {
        /* If we get here, the JPEG code has signaled an error.
         * We need to clean up the JPEG object, close the input file, and return.
         */
        //jpeg_abort_decompress(&cinfo);
        jpeg_destroy_decompress(&cinfo);
        return;
    }

    /* Now we can initialize the JPEG decompression object. */
    jpeg_create_decompress(&cinfo);

    /* Step 2: specify data source (eg, a file) */

    jpeg_filerw_src_init(&cinfo); ;

    /* Step 3: read file parameters with jpeg_read_header() */

    (void) jpeg_read_header(&cinfo, TRUE);
    /* We can ignore the return value from jpeg_read_header since
     *   (a) suspension is not possible with the stdio data source, and
     *   (b) we passed TRUE to reject a tables-only JPEG file as an error.
     * See libjpeg.txt for more info.
     */

    /* Step 4: set parameters for decompression */

    /* In this example, we don't need to change any of the defaults set by
     * jpeg_read_header(), so we do nothing here.
     */
    cinfo.dct_method = JDCT_IFAST;
    cinfo.do_fancy_upsampling = 0;
    cinfo.out_color_space = JCS_RGB;
    /* Step 5: Start decompressor */

    (void) jpeg_start_decompress(&cinfo);
    /* We can ignore the return value since suspension is not possible
     * with the stdio data source.
     */

    /* We may need to do some setup of our own at this point before reading
     * the data.  After jpeg_start_decompress() we have the correct scaled
     * output image dimensions available, as well as the output colormap
     * if we asked for color quantization.
     * In this example, we need to make an output work buffer of the right size.
     */
    /* JSAMPLEs per row in output buffer */
    row_stride = cinfo.output_width * cinfo.output_components;
    /* Make a one-row-high sample array that will go away when done with image */
    buffer = (*cinfo.mem->alloc_sarray)
             ((j_common_ptr) &cinfo, JPOOL_IMAGE, row_stride, 1);
    /* Step 6: while (scan lines remain to be read) */
    /*           jpeg_read_scanlines(...); */

    /* Here we use the library's state variable cinfo.output_scanline as the
     * loop counter, so that we don't have to keep track ourselves.
     *///printf("w=%d, h=%d\n", cinfo.output_width, cinfo.output_height);

    uint32_t index_last = 0;

    while (cinfo.output_scanline < cinfo.output_height) {
        /* jpeg_read_scanlines expects an array of pointers to scanlines.
         * Here the array is only one element long, but you could ask for
         * more than one scanline at a time if that's more convenient.
         */

        (void) jpeg_read_scanlines(&cinfo, buffer, 1);
        /* Assume put_scanline_someplace wants a pointer and sample count. */
        uint8_t *inbuffer = buffer[0];
        uint32_t index;
//        static uint32_t index_last = 0;


        uint32_t y = cinfo.output_scanline;
        //uint16_t *out = NULL;
        uint16_t *out = (uint16_t *)outbuffer;// + (y * cinfo.output_width);

        for (index = 0; index < cinfo.output_width; index++) {
        uint16_t c = ((*inbuffer) >> 3) << 11 | ((*(inbuffer + 1)) >> 2) << 5 | (*(inbuffer + 2)) >> 3;

#ifdef CONFIG_LCD_INTERFACE_I2S
 a      out[index_last+index] = c;
#else
        out[index_last+index] = c >> 8 | c << 8;


#endif
        inbuffer += 3;
        }

        index_last += index;

//        if(!(y % CONFIG_LCD_BUF_HIGHT) || index_last >= (CONFIG_LCD_BUF_HIGHT*cinfo.output_width)){
//            lcd_cb(0, y-CONFIG_LCD_BUF_HIGHT, CONFIG_LCD_BUF_WIDTH, CONFIG_LCD_BUF_HIGHT, outbuffer);
//            index_last = 0;
//        }
    }


    /* Step 7: Finish decompression */
    (void) jpeg_finish_decompress(&cinfo);
    /* We can ignore the return value since suspension is not possible
     * with the stdio data source.
     */

    /* Step 8: Release JPEG decompression object */

    /* This is an important step since it will release a good deal of memory. */
    jpeg_destroy_decompress(&cinfo);
}
